|
|||||
|
|
Ab initio study of ultra-incompressible ternary BeCN2 polymorph |
|
| Authors: | Haiyan Yan Shaomei Chang |
| Affiliation: | a Department of Chemistry and Chemical Engineering, Baoji University of Arts and Sciences, Baoji 721013, PR China b School of Science, Xidian University, Xi’an 710071, PR China c Nonlinear Research Institute, Baoji University of Arts and Sciences, Baoji 721007, PR China d Department of Physics, Northwest University, Xi’an 710069, PR China |
| Abstract: | The structural, mechanical, thermodynamic, and electronic properties calculated by projector-augmented wave method are presented for BeCN2 in chalcopyrite and wurtzite-like structures. The calculated high bulk modulus (321 and 309 GPa) and large shear modulus (302 and 298 GPa) suggest that they are ultra-incompressible and hard materials. The ultra-incompressibility is attributed to a stacking of strongly three-dimensional covalent bonded CN4 and BeN4 tetrahedrons connected by corners. Thermodynamic study demonstrates that these two structures can be synthesized at ambient condition. Furthermore, the structural transformation from the wurtzite-like to the chalcopyrite phase was predicted at about 17 GPa according to the enthalpy difference calculations. |
| Keywords: | D. Crystal structure D. Elastic properties D. Thermodynamic properties D. Electronic structure |
| 本文献已被 ScienceDirect 等数据库收录！ | |